Grinding machine



Dem-6, .1927'.

GRINDINQ MACHINE `Led Nov. `6, 1924 E. B. GARDNER T AL .Jay

6,1927'.` f l l I' 1,651,382 E. B. GARDNER E'I'lr GRINDING MACHINE l'Filed Nov, e, 1924- s sheets-sheet 2 Patented Dec.` 6, 1927.

n UNITED STATES,

l l 1,651,332 PATENToFFicE.

EDWARD B. GARDNER, JOHN N IELsEN, AND RALPH D. GAaDNEIaor :canoral WISCONSIN.

GBINDING MACHINE.

This invention pertains to grinding machines and is more particularly related to those machines wherein Opposed grinding wheels are adapted to simultaneously work on two or more faces of an article .disposed between them.

Our machine is primarily adapted to grind the ends of rods, tubes, 'bars and the like, to smooth or completely finish them as desired. It is particularly and peculiarly adapted to grind-the ends of valve stems, push-rods and other automotive mechanism which may require a ,standard length for a large num- I ber of like parts and may require that the ends be iinishedat particular angles With respecty to one another. While we are aware that Patent #878,685 issued February 11, 1908, discloses a machine for grinding the ends of corncob pipes, this machine, while in somerespects is similar to oui1 own, is not adaptable for our vpurposes nor could it be arranged therefor. For this and other reasonswe have devised a machine tol be hereinafter described, embracing within its broader aspects novel and invaluable features.

In-view ofthe foregoing, it is an object.

to provide a machine which will nish the ends of bar, rod, or other Stock in any manner desired and which will be automatic in its operation.

Another object is to provide a machine construction whereby the ends of the-stock, regardless of its character, may be/jinished fiat and parallel at substantially any angle to the stock sides.

Still another object is to providea continuously operating automatic wherein the work is automatically fed, guided, positioned, clamped, ground or finished and discharged.

Further objects will be readily appreciated from the description and claims and from the drawing in which:

Fig. 1 is a front elevation of the grinding machine shown in Fig. 2, taken along the line 2 2 the; scf and embodying a preferred form oi our invention,

Fig. 2 is a left-hand end elevation of the machine shown in Fig. 1,

Fig. 3 is a partial section taken along the line 3--3 of Fig. 1, showing the feed mechanism and work-holding chuck, and,

machine.

e Fig. 4 is a top plan view of a part of the number of preferred mechanisms which may be classified and described separately, but which cooperate one with the other for the attainment of the foregoing objects. For convenience we will hereinafter refer to them under the headings Grinding wheels, lVork holding chuck, and Feedchute.

Grinding wheels. s

Mounted upon any suitable foundation or bed 2 is a table 4 upon which similar standards 5, mounted upon reciprocal carriages 6 and 8, carry the grinding wheels 10 and A12 with their associated mechanism. The grinding wheels are arranged to be drivenl through the medium of pulleys 14 andA 16vsecured to the respective wheel shafts 18 and 20 carried in bearings 22, 24, 26 and 28. The carriages 8 lare constructed to reone another upon the table 4, which is provided with dovetailed portions 30 for guiding and sliding engagement, the reciprocating movements being imparted to the carriages by suitable mechanism including a rockshaft 32 normally urged in one direction to cause an'y approaching movement of the wheels by means of an arm 34 fixed thereto and actuated by a weight 36 suspended therefrom. `Relative pressure exerted by the grinding wheels upon work positioned therebetween may be varied by increasing or decreasing the number of weights 36.

Thespecific mechanisms connecting the rocksla'ft -32 and the carriages 6 and 8 whereby the carriages are moved from one another by the shaft, may be of any preferred construction although we have shown them of a similar form to that illustrated and described in the patent to Ralph D. Gardner, No. 1,465,762, issued August 21, 1923. Since ready reference may be had to this patent for a full understanding of the carriage reciprocating mechanism, it .is deemed unnecessary to further describe it herein, except to say that the lshaft 32 may be rocked by hand by means of handle 38 or through the medium of the arm 40, cam

`42 and gearing (not shown) in a counterclockwise direction t0 move the grinding wheels apart. The gearing is inclosed within the gear box 44 .and connected through shaft 4 6 and pulleys 48 with any Suitable source of power. The approaching move` ment of the grinding wheels is limited by an abutment bar 50, carried by one of the carriages 6 ,or 8, and adapted to abut against an adjustable micrometer abutment screw 52, carried by the other of said carriages.`

The grinding wheels may be adjusted to dispose them into or out of exact parallelism A as desired, for purposes that will be obvious. lith this end in View the standards 5 may be moved laterally of the carriages 6 and 8 by loosening opposed set screws 53 arranged in opposed relationon opposite sides of the shafts 1S and 20. The wheels may also be adjusted for vertical alignment by loosening a securing bolt 5d and turning adjustment nut 55. '.l`he details of the mechanisms for procuring vertical and lateral adjustments have not been further shown and described herein 4because reference may be had to the copending application of Ralph D. Gardner, Serial #648216, .tiled June 2S, '1923 for a full disclosure.

Wow/c holding chile/a'.

Mounted upon the bed t of the machine is a single standard bifurcated to form arms 62, 64, (a pair of standards may be used) in which are journaled the ends of shaft 66, upon which a chuck 68 is lixedly secured for rotation therewith.v The chuck 68 is preferably positioned equidistantly between the extremities of inward movement of' the grinding wheels toward one another and is arranged to project the work into engagement with the surfaces of the grinding wheels as it revolves. This is more particularly illustrated in Figures 3 and 4. To one end of the shaft 66 a gear 70 is secured and adapted to engage with a train of gears within the gear box 4l. A housing 72`is disposed about the gear 70 and in connection with the gear box ..44 for safety purposes.

Bearing upon the shaft 66, but lixedly connected in any suitable manner with the stationary frame of the machine is a' cam 74 arranged in the path of 'a plurality of levers or cam followers 76, each of which is pivoted as at 7S upon the body of the chuck or work carrier (3S. Each lever 76 carries at its inner end a roller or other similar anti-friction arrangement for engagement with the cam face of the cam T4 as it is revolved thereabout, and each follower is urged into contact with the cam face by means of a plurality of springs or other tension devices 79 secured at their inner ends to thehub of the chuck 68 and atV followers, at their outer ends, carry a movable jaw or work clamp S0, cooperative with a lixed jaw S2, each of which jaws is provided with a suitable slot whereby the work may be gripped between them. Both the lined and movable jaws may be made removable for replacement by other cooperative jaws in -accordancewith the varying characteristics of the work to be received thereby.

Feed chate.

Forming a part of the standards 62 and G4 or rigidly secured thereto are a pair of arms 84 and St'coiinected by cross members S8 and 90 `to the latter of which a pair of links 92, connected by a transverse member 94, are adjustably secured. By varying the angular relation of the links 92 with respect to the projecting arms 84 and 86, the inclination ot the work feed chute 96 is varied as will be clearly observed from the showing of Figure 2. This chute is secured to a bracket tnot shown) pivoted upon the transverse member S6 and may be locked in any desired position by means of set screws 98 which pass through blocks 100 disposed on opposite sides of the gravity chute and which screws, in addition to the locking function stated, serve to iixedly buf adjustably secure a pair oi guides 102 arranged on opposite sides for guiding the work as it passes downward. Additional blocks 104 may be provided at intervals along the length of the chute, if desired, and in some instances it may be found desirable to pro-z vide a guide and baille plate 106 arranged to extend transversely across the chute to prevent overrunning of round pieces of work. A second guide member 108 may be placed transversely across the chute adjacent the work receiving chute. In operation, the guides 102 are moved toward or away from one another to accommodate the length of the work passing therebetween. The chute 96 is adjusted upwardly or downwardly in accordance with the desire of the operator 4or the frictional characteristics` of the work so that when the machine is started the work will automatically feed itself between the guides and into the open jaws of the chute.

The cam mechanism of the chuck is so arranged that the jaws will be opened prior to their coming adjacent to the feed end of the feed chute, will be closed shortly after leaving the chute, and will be held closed thereafter and until the work has passed the grinding surfaces to a point where they oper to discharge the work into a hopper or the like, (not shown).

It sometimes happens that the work in passing out of the feed chute into the jaws may become slightly displaced and overhangs one side of the chuck to a greater extent than the other. If such an accident should occur, it would not only result in undue wear of one grinding surface, but would be apt to distort the work and'put undue wear on the :bearings and carriage mechanism of the machine. To obviate this, -we have arranged a `work positioning device comprising a pair of adjustablebrackets 110 and 112 to which positioning 'guides 114:, 116 are securedin opposed relation. These two guides 114and 116 are inthe form of plates bent outwardly at their outer or feed ends and project inwardly inl substantially parallel planes to a point beyond the position at which the clam ing jaws of the chuck are arranged to be tlghtly closed. by the cam. In this way thev Work is'positioned in the chuck jaws with its ends projectin substantial-ly equal distances on each si e thereof and held in this position until the chuck jaws rigidly clamp it for the grinding op- A eration.

For the purpose of A'dressing the faces of the grindin wheels when necessary, and so that itmaye done during the eriod of operation of the machine we pre er to mount a dresser'comprising an adjustable bracket 118 upon a portion of the bed 4 in order to support and guide a4 wheel dressing bar 120, adjustably therein. Since this dresser vforms no part of the present invention, but is adaptable totheu'general combination there- .and claimed in a copending application,Se rial No. 648,217, liled June 28, 1923, it will not be further described herein.

From the foregoing description,l the optionin'g guide-ways adjacent t arly illustrated, described,

eration of our machine should be readily understood together with its many attendant advantages. We do not, therefore, desire to be limited to the particular mechanisms or their arrangement, but only by the spirit of our invention and the scope of the appended claims. We claim:

1. In a grinding machine 'in combination, a air of opposed grinding wheels, a movab e carriage for each wheel, means for automatically moving said wheels toward and from one another, a ositive adjustable stop mechanism associate with said carriage for limiting the approach of said Wheels, and endless work holding means rotatably carried between said wheels.

2. In combination, a pair of opposed grinding wheels, a movable carriage for each wheel, means for automatically moving said wheels toward and from one another, means for adjusting the angle at which said wheels lapproach one another, means for limiting the approach of said Wheels, a work holder adapted to carry work into and out of engagementwith said wheels, means for automatically clamping) holder, and adjusta le but ri id Work posige work holder and arranged to guide vwork received in said holder until the work is carried linto engagement with said wheels.

EDWARD B. GARDNER. J ORN NIELSEN. RALPH D. GARDNER.

work in said work 

